Checkout is only one part of the workflow.
A payment feature needs to connect the provider transaction to your order, account or subscription. Think through the whole journey: starting checkout, confirming payment, granting access and explaining the result to the customer.
Do not rely only on a browser redirect to confirm payment. A customer can close the browser or lose connectivity while a payment event is still being processed. The backend needs an appropriate verification process using the provider’s supported mechanism.
Define the commercial rules first
Document what is being sold, when access begins and how changes are handled. Subscription logic needs to match the customer promise and the chosen provider’s capabilities.
- One-off purchases, recurring subscriptions or a combination.
- Plan upgrades, downgrades and when the new entitlement starts.
- Failed payments, retries and any grace period.
- Cancellations, refunds and the effect on product access.
- Transaction records and reconciliation for your operations team.
Make events safe to process more than once
Webhook events can be delayed or delivered more than once. A robust integration verifies their source and prevents the same event from creating duplicate orders or account changes.
Record the provider references and processing outcome. Failed updates should be visible and recoverable. This gives your support team a way to explain what happened when the app and payment provider appear to disagree.
Choose a provider around the actual business model
Compare provider support for your location, payment methods, recurring billing and settlement requirements. Confirm current fees and eligibility directly with the provider during discovery.
Use supported hosted checkout or tokenisation where appropriate, and avoid placing secret credentials in the browser. Specialised wallets, escrow and investment products need their provider and specialist requirements resolved before treating them as ordinary checkout integrations.
Make it specific to your business
Explore payments, wallets & subscriptions, apis & system integrations, e-commerce & marketplaces to find a relevant starting point, then tell us what you want to achieve.